How social frailty is operationalized matters: Relationships with health and wellbeing in late adulthood.

Objectives: There are currently major inconsistencies in the methodological approaches used to index social frailty. The present study aimed to better understand which of these approaches may be most valuable in predicting older adult's physical health and psychological wellbeing.

Design: One hundred and thirty-three participants aged 60-90 years completed five measures commonly used to index social frailty, along with five measures of physical health, and psychological wellbeing. Social frailty was not only assessed at the scale level but was also considered in terms of both the objectivity (versus subjectivity) of each scale item, and at the social concept level (whether each item captured lifestyle, living alone, loneliness, social activities, social network, social role, social support, or sociodemographic characteristics).

Results: As predicted, subjective social frailty accounted for the largest share of explained variance of psychological wellbeing in older adults, relative to objective indicators and key demographics. However, contrary to hypotheses, objective social frailty failed to uniquely predict physical health. Further analyses revealed that the predictive value of subjective social frailty was driven primarily by feelings of loneliness.

Conclusions: The present study provides novel insights into how operationalizations of social frailty vary in terms of their relationship with important indicators of real-life function. The findings have direct implications for the development of targeted interventions focused on reducing social frailty in late adulthood.